Sauté the Vegetables: In a large stockpot or Dutch oven, heat the olive oil and butter over a medium heat. Once the butter has melted, add the chopped onion, celery, and carrots. Sauté for 6-8 minutes, stirring occasionally, until the vegetables have softened and the onion is translucent. Add the minced garlic and dried thyme and cook for another minute until fragrant.

Make the Roux: Sprinkle the plain flour over the softened vegetables. Stir continuously for about 2 minutes to cook out the raw flour taste. This paste, known as a roux, is what will thicken our soup.

Create the Soup Base: Gradually pour in the warm chicken stock, about 200ml at a time, whisking constantly as you add it. This slow addition is crucial for a smooth, lump-free soup. Once all the stock is incorporated, bring the mixture to a gentle simmer.

Simmer and Thicken: Let the soup simmer gently for 10 minutes, uncovered, stirring occasionally. The soup will begin to thicken nicely.

Add Cream and Chicken: Reduce the heat to low. Slowly pour in the double cream, stirring as you go. It's important not to let the soup boil after this point, as it can cause the cream to split. Add the shredded chicken, salt, and pepper. Let it warm through for 2-3 minutes. What works best for me is tasting and adjusting the seasoning at this stage, before adding the gnocchi.

Cook the Gnocchi: Add the potato gnocchi to the pot. Increase the heat slightly to a gentle simmer (but not a rolling boil). Cook for 3-4 minutes, or until the gnocchi float to the surface. They cook very quickly!

Wilt the Spinach: Turn off the heat. Stir in the fresh spinach. The residual heat of the soup will be enough to wilt it perfectly in about a minute without it becoming overcooked.

Serve Immediately: Ladle the hot soup into bowls. Garnish with a little extra black pepper or some grated Parmesan cheese if you like, and serve straight away.